Once upon a time, we were told losing weight required nothing more than a good diet and exercise plan and the motivation to stick with both.

While those things are still true, an entire industry has sprung up to help us achieve those goals. And over the past few years, dieting has gone high-tech, with an assortment of devices and services designed to help us shed the pounds. Many attempt to turn electronic items we use already, like cell phones, MP3 players, computers, and personal digital assistants (PDAs), into weight loss aids.

But is this high-tech approach for you? More important, could it really help you lose those extra pounds or build those six-pack abs?

The answer, it seems, depends on the gadget -- and on you.

"If something helps you make healthy lifestyle changes, and you can maintain those changes, then it's always a good thing," says New York University nutritionist Samantha Heller, MS, RD.

In fact, a study presented at an obesity meeting in October 2005 showed that listening to music while you work out may help you stick to a fitness plan and boost weight loss.

That said, Heller cautions that many of the devices on the market may be unrealistic, not only in terms of cost but also in what they can accomplish -- particularly when it comes to helping us make permanent changes in our eating and exercise habits.